The present invention relates to surfactants particularly those for use in contact with the human or animal body.
A bath product which has been increasingly popular is the Bath Bomb® or Ballistic® These products are primarily designed to provide an experience for the user. They contain sodium bicarbonate and citric acid such that on contact with water they effervesce carbon dioxide. This effervescence provides a pleasant sensation for the user. The products also typically contain oils and/or fragrances which are liberated with the effervescence. This liberation adds to the sensory experience of the user.
Surfactant products such as bubble baths, shampoos, shower gels and toothpastes are extremely well known cosmetic products and personal care products. Bubble bath products are typically provided in the form of liquids. They are sold in containers to the end user and may be dispensed by the end user. However, the required use of packaging is a disadvantage. From an environmental perspective, waste packaging is a significant problem, despite the availability of recycling. For this reason at least, solid materials for creating bath foam have become increasingly popular. These solid surfactant materials may be in the form of a Bubble Bar®. For example WO00/47181 discloses a surfactant product bubble bar which is solid and in the form of a tablet or bar. When required for use, a portion of the solid product may be ‘broken off’ the bar and used. The products of WO00/47181 are formed from a composition containing cream of tartar, sodium bicarbonate and a surfactant. Although these products address environmental concerns they suffer certain disadvantages. For example, in use the user must apply the required amount of product to the bath water, for example by holding the solid product under running water. In this way, the required foam is produced. Furthermore, some users may find that they do not provide the same ‘experience’ that a bath ballistic may provide.
These problems are addressed in the teaching of WO2011/154727. In this document a two layer bath ballistic type product is disclosed having two effervescent layers. The outer layer is a bath ballistic type material which vigorously effervesces on contact with water and the inner layer is a mixture of bubble bar type material and bath ballistic material. This inner layer contains a surfactant and when contacted with water more gently effervesces than the outer material and thereby gives off bubbles when the water combines with the surfactant.
The present invention seeks to provide products which provide a bath with an enhanced experience by the user.